Agenda - Public Works Committee - 04/21/2009

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4.0 OEVELOPtNGRECOMMENDE.DCHANGES TO SPEED LIMIT STATUTETEXT~ Through the cgurse ofwol'k by the TaskForce, the members explored several options and alternatives f9restablishing revisionstb the speedlitnit statutes. Many of these alternatives and discussions centered 9n the question of "what is the proper statutory speed limit" .and what might be. a basis for changing it from its present value. A.relatedquestion is whether the speed Ihnitshould vary for different types of Hlowel' speed"roadways. The groupexpJoted the issue of whether roadways could be differentiated so that "pure residential" streets could have a statutory 25 MPH limit while collectors, arterials .and .. \ above couldi9ec~setNa statutory 3 OMPH. No alternative waS developed that would likely be acceptabl~toa:Ilstakeholders (e.g., citizens, politicians, enforcement, engineers, etc.). In particular,thel~w enforcementcommunity opposed having a dual-level set of statutory. speed limitswithin.a.n {Jtban District (or similarly defined) area. Similarly,di$cussions.were held about setting statutory speed limits on some other basis (e.g., functionaFclassification or geographic boundary such as within the seven-county. metro area or within the Minneapolis/St.Paul urban core). However, this was found to go against the principle of uniformity. One of the important principles that the Task Force supported is that speed limit setting should be uniform state-wide and should notvaryJrom city to city or in different parts of the state. . . " The work of the committee therefore focused on how toarnend the speed limit statutes without creating a significant change in the approach to setting speed limits and without causing a oomplete overhaul of the speed limit statute text. 4.1 Urban District . 4.1.1 Urban District Discussion Many factors were examined in considering what the appropriate statutory speed limit. . should be in Minnesota for the Urban District or "l,ow speed" roadways. Withinthe Task Force this essentially represented an analysis of "25 vs. 30" far the statutory limit. One of the first issues to be considered was the engineering, or basic safety. element. A key point within the safety discussion is the concept of "survivabiliJY." ... Data were presented to the Task Force that depicted survival rates for pedestrians for vehicle/pedestrian crashes atvarying speeds. It is intuitively clear that the highertbe travel speed of the car, the more critical a vehicle/pedestrian conflict would be. Thus, survivability rates decline as speeds increase. The graph shown in Figure 2~2. (Section 2 of the report) depicts the survival rates as a function of vehicle speed. A change in travel speed from 30 to 25 does cause an incremental change in survivability. However, given the limited number of pedestrian fatalities on low- speed roads in Minnesota, to obtain significant changes in survivability would require a decrease of travel speeds to 20 :- or lower. It was further concluded that there would not possibly be overall support for a statutory speed limit of 20 J\1PH nor complial'lce with this speed. Basing a decision on speed limit solely on the issue of pedestrian survivability in a crash event would not yield an acceptable limit. . Page 20 47